High-tension rectifying apparatus.



H. C. SNOOK.

HIGH TENSION RECTIFYING APPARATUS.

APPLICATION FILED JAN.8, 1911.

Patented Dec. 25,1917.

2 SHEETS-SHEET 1.

H. C. SNOOK.

HIGH TENSION RECTIFYING APPARATUS.

APPLICATION FILED IAN.8, I9I7. ggmlgg Paaented Dec. 25,1912.

2 SIIEETS-SHEET 2.

HOMER CLYDE, SNOOK, OF OAK PARK, ILLINOIS.

HIGH-TENSION RECTIFYING APPARATUS.

Specification of Letters Patent.

Patented Dec. 25, 1917.

Original application filed April 13, 1909,.Seria1 No. 489,551. Renewed November 9, 1916, Serial No. 130,476. Divided and this application filed January 8, 1917. Serial No. 141,072.

To, all. whom it may concern.-

Be. it known that I, HOMER CLYDE SNooK, a citizen of the United States, residing at Oak Park, Illinois, have invented certain new and useful Improvements in High-Fem sion Rectifying Apparatus, of which the following is'a specification.

My invention relates to apparatus for delivering high potential uni-directional current to an X-ray tube or other translating device, or to a consumption circuit.

This application is a division from my application serial number 489,551, filed April 13, 1909, renewed November 9, 1916, serial number 130376. I

My invention resides in apparatus involving a switch for rectifying high potential alternating currents for general use, and particularly for the excitation of X-ray tubes, which require uni-directional current, the source of alternating current being either polyphase or single phase.

The switch structure is such that for each single phase the relatively moving and fixed contacts co-act in a single plane and n synchronism with the alternating current, a plurality of switching elements being provided when polyphase current is employed.

For an illustration of some of the forms directional currentwaves and their resultant.

Referring to Fig. 1, L and L are. the conductors of an electric supply circuit leading to the motor side M of a motor generator or inverted rotary R, whose generator side G delivers three-phase alternating current to the threeconductorsl, 2 and 3 through the adjustable resistances 4,v preferably non-1nductive, to the primary windings p 12 and p of the threesphase transformer T havmg the high potential secondaries s s -and 8f, here shown as Y.-connected and having their omm terminal connected to the earth 6..

by conductor 5. The three transformer secondaries have their other terminals connected through the high frequency choke coils D, serving to prevent any parasitic high frequency oscillations running back to and puncturing the insulation of the secondary windings, with the roller or other brushes of a high tension rectifying switch H comprising the three disks to, w and c0 of insulating material capable of withstanding the high potentials involved, there being one of these insulating disks for each phase of the transformer secondary current. The transformer T is preferably of'a type having low magnetic leakage. Set into the insulating disk w is a conducting are 41 which extends entirely through the disk 10 and has an exposed face on each side of the disk. On one side of the disk, the front, for example, are arranged the four roller brushes or other contacting devices 42, all electrically connected together and to a terminal of the secondary 8 On the opposite side of the disk, the rear, for example, are the two pairs ofopposed roller brushes or similar contacting devices, one pair 43, 43 connected to the conductor 23, and a similar pair 44, 4A, disposed at right angles to the first pair and both electrically connected to the con ductor 24, the conductors 23 and 2% bein the consumption circuit including the X-ray tube X, or other suitable translating device, an ammeter F being included in such circuit if desired. The three disks 10 10 and w are all mechanically connected to a common shaft 29, driven in synchronism with the alternating current, as by coupling said shaft, Fig. 3, by a coupling 35 to the shaft 34: driven by a synchronous motor or con-v stitutingthe shaft of the converter or generator R or Gr.

The second disk 10 has a conducting arc 45in a different angular position with respect to the driving shaft than the are 41 of the disk w lVith the disk 10 are associated the brushes 46 on the front side, all connected together and to the terminal of the secondary 8 On the rear the opposing pair of similar contacting devices 47 are electrically connected to the conductor 23, and the pair 48 disposed at right angles to the pair 47 are electrically connected to the conductor 24. of the third disk w there is a third con- And similarly, in the case ducting are 49 with which cooperate the four brushes 50 on the front side, all connected to a terminal of the secondary s and on the rear side the brushes 51 connect with the conductor 23, and the second .pair 52, at right angles, are connected with the conductor 24. As here shown, for three-phase working, each of the arcs 41, 45 and 49 has an angular or circumferential extent of substantially 60 degrees, corresponding with substantially 120 electrical degrees,the shaft 29 rotating the disks making one half revolution for one c01n;. lete electrical cycle. The arcs 41, 45 and 49 are shifted with respect to each other substantially 60 mechanical degrees or 120 electrical degrees.

The disks and the associated brushes may be submerged in oil, air, or gas under pressure, or in any medium having higher insulating power than air. In Fig. 3 the submergence is shown in oil contained in the tank 40.

In operation the disks are rotated at synchronous speed, and the arcs4l, 45 and 49 close circuit between the opposed brushes or contacting devices and bring the consumption circuit 23, 24 into communication with the secondaries of the transformer T in a predetermined order of succession and at certain relative times such that the consumption circuit receives high potential unidirectional current.

In Fig. 2 is shown a modified form of switching mechanism, the primaries and primary circuits of the transformer T being omitted. In this case there is diametrically opposed to each of the arcs 41, 45 and 49 a second are 41*, 45 and 49 and in con sequence half of the brushes or roller contacts may be omitted, so that there are two pairs of front and rear contacts at right angles to each other. The effect, however, is the same in that only uni-directional high potential current impulses are delivered to the consumption circuit 23, 24.

In both the arrangements of Figs. 1 and 2 there are supply *ircuit terminals or brushes, as 42, 46 and 50, and consumption circuit terminals or brushes, as 43, 44, 47, 48, 51 and 52, the conducting elements or arcs rotated by the disks affording electrical communication between the supply circuit terminals and the consumption circuit terminals to cause in the consumption circuit uni-directional current flow.

In the arrangements of both Figs. 1 and 2 the switching mechanism H rectifies the current in each of the three phases so that there are, in effect, in a consumption circuit. overlapping half waves, all of the same polarity. These overlapping half waves then cause in the consumption circuit uni-directional impulses of a frequency triple the frequency of one half cycle supplied by the transformer T. And this triple frequency current has a potential or voltage which is higher than the voltage delivered by any one of the secondaries s .9 or 8 The effect is graphically illustrated in Fig. 4, wherein the overlapping half waves are indicated at a, 7), c, a, b, and 0, of which a, b and 0 represent the positive half waves of the three diflerent phases, and a, 7), and 0 represent the turned over or negative half waves. The switch relations are such that each transformer secondary is in circuit for each half wave for a time corre sponding with the length (Z. There results in the circuit of the tube X a fluctuating current of frequency triple to the frequency of a half cycle of one phase supplied by the transformer T, this triple frequency current being represented by the curve 6 in the up per part of Fig. 4.

Each of the arcs 41, 45 and 49 may be less than (50 mechanical degrees or 120 electrical degrees in extent, but they preferably should be made substantially ('30 mechanical degrees or 120 electrical degrees in length for a three-phase system.

lVhile I have in the drawings disclosed a three-phase system and apparatus, it is to be understood that my system and rectifying apparatus are adaptable also to a single phase current or to a current of any num ber of phases.

lVhere the switching apparatus is submerged in oil or other medium, as described in connection with F 3, the mechanical dimensions of the parts may be reduced and still with safety operate at potentials of from 50,000 to 150,000 volts.

hat I claim is:

1. A )paratus for rectifying high potential alternating current comprising supply circuit and consumption. circuit terminals, an insulating disk rotating in synchrouism \uith the alternating current, and conductin means carried by said disk for affording electrical communication between said supply and consumption circuit terminals, said terminals consisting of rollers adapted to engage said means, cooperating supply and consumption circuit terminals being disposed on opposite sides of said disk.

2. Apparatus for rectifying high potential alternating current comprising supply circuit and consumption circuit terminals consisting of rollers, an insulating disk mechanical degrees with respect to each other, each pair comprising a supply cir- 'cuit and a consumption circuit terminal, a conductor rotatable in a single plane for bringing said pairs of terminals into communication with each other in succession, and means for rotating said conductor in synchronism with the alternating current.

4:. Apparatus for rectifying high potential alternating current comprising a plurality of pairs of terminals, each pair comprising a supply circuit and a consumption circuit terminal, and a conductor rotatable in a single plane for bringing said pairs of terminals into communication with each other in succession, said pairs of terminals beingdisposed at 90 mechanical degrees with respect to each other.

5. Apparatus for rectifying high potential alternating current comprising a plurality of pairs of terminals, each pair comprising a supply circuit and a consumption circuit terminal, a pair of conductors insulated from each other and rotatable in a single plane for bringing said pairs of terminals successively into electrical conmmunication with each other, said pairs of terminals being disposed at 90 mechanical degrees with respect to each other and said conductors disposed at 180 mechanical degrees with respect to each other and making one half revolution per electrical cycle.

6. Apparatus for rectifying high potential alternating current comprising two pairs of terminals disposed at 90 mechanical degrees with respect to each other, each pair comprising a supply circuit and a consumption circuit terminal, an insulating disk rotating in synchronism with the alternating current, and a pair of conductors insulated from each other and carried by said disk and adapted to bridge said pairs of terminals in succession.

7. Apparatus for rectifying high potential three-phase alternating current com;- prising for each phase a conductor, means for rotating said conductor in synchronism with the current in a single plane, and supply and consumption circuit terminals dis posed at 90 mechanical degrees with respect to each other and adapted to be brought into electrical. communication with each other through said conductor, said conductors for the different phases being displaced substantially 120 electrical degrees from each other.

8. Apparatus for rectifying high poten tial three-phase alternating current comprising for each phase a conductor rotatable in synchronism with the current in a single plane, and supply and consumption circuit terminals adapted to be brought into electrical communication with each other through said conductor, said conductors for the different phases being normally insulated from the supply and consumption cir cuits and displaced substantially 120 electrical degrees from each other, each conductor having an electrical extent of approximately 120 electrical degrees.

9. Apparatus for rectifying high poten tial three-phase alternating current comprising for each phase an insulating disk, a conductor carried thereby and extending to opposite faces thereof, supply and consumption circuit terminals disposed on opposite sides of said disk and adapted to communicate through said conductor, means for driving said disks in synchronism with the alternating current, the conductors of the different disks being normally insulated from the supply and consumption circuits and displaced substantially 120 electrical degrees from each other.

10. Apparatus for rectifying high potential three-phase alternating current comprising for each phase an insulating disk, a conductor carried thereby and extending to opposite faces thereof, supply and consumption circuit terminals disposed on opposite sides of said disk and adapted to communicate through said conductor, means for driving said disks in synchronism with the alternating current, the conductors of the difierent disks being normally insulated from the supply and consumption circuits and displaced substantially 120 electrical degrees from each other, said conductors each being substantially of 120 electrical degrees extent.

11. Apparatus for rectifying high potential three-phase alternating current comprising an insulating disk for each phase, diametrically opposed conductors carried by said disk, pairs of supply and consumption circuit terminals disposed at 90 degrees with respect to each other and cooperating with said conductors, means for rotating said disks in synchronism with the alternating current at a rate of one half revolution per electrical cycle.

In testimony whereof I have hereunto affixed my signature this 5th day of J anuary, 1917.

HOMER CLYDE SNOOK.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

